4-Chloro-2,5-dimethoxyamphetamine or 2,5-dimethoxy-4-chloroamphetamine or 4-Chloro-2,5-DMA or DOC is a psychedelichallucinogenic drug of the phenethylamine family. Used by some as an entheogen, DOC was presumably first synthesized by Alexander Shulgin. The drug is generally taken orally, but some users have been known to insufflate or smoke the pure powder.

A normal average dose of DOC ranges from .5-8.0 mg; the former producing threshold effects, and the latter producing extremely strong effects. Doses up to 10mg have been known to send the user into a restless stupor. Onset of the drug is 1-3 hours, peak and plateau at 4-8 hours, and a gradual come down. After effects can last well into the next day.

Unlike simple amphetamines, DOC is a psychedelic that resembles LSD, DOB, and amphetamines. These effects include open and closed eye visuals, increased appreciation of music, increased awareness of sound and movement and euphoria.

The toxicity of DOC is not known, but nausea, chestpains, and vasoconstriction have been reported by some users. In June 2006 four teenagers were admitted to a hospital in Metropolitan Detroit, Michigan after accidentally overdosing DOC.[1] To date, there have been no deaths attributed to DOC. However, DOC is an extremely potent psychoactive, and the risk of overdose is great if unknown or extreme dosages are taken.

Although rare on the black market, sales of DOC on blotterpaper and in capsules was reported in late 2005. DOC is sometimes misrepresented as LSD by unscrupulous dealers. This is particularly dangerous, as DOC is not known to have the safety profile of LSD.

4-chloro-2,5-dimethoxyamphetamine is unscheduled in the United States. It is likely that it would be considered an analogue (of DOB or DOM), in which case, sales for human consumption or possession with the intent to ingest could be prosecuted under the Federal Analogue Act. In the United States, the analogues 2,5-dimethoxyamphetamine, 4-bromo-2,5-dimethoxyamphetamine, and 4-methyl-2,5-dimethoxyamphetamine are Schedule I controlled substances. DOC is scheduled in many other countries including Canada, Germany, New Zealand, Sweden and the UK.